The U.S. is struggling to shore up its “rebalance” policy toward the Asia-Pacific as China strengthens its regional influence and with skepticism lingering over its much-trumpeted refocus on the strategically vital region.

At the core of the efforts is strengthening Washington’s security cooperation with its key allies of South Korea and Japan, and crafting a systematic mechanism for trilateral defense collaboration ― a reason why U.S. Defense Secretary Ashton Carter traveled to Seoul and Tokyo last week.

Carter’s weeklong trip to Asia came as China has sought to bolster its regional influence through various initiatives such as the establishment of the Asian Infrastructure Investment Bank, seen as a counterbalance to the U.S.-led financial institutions, and what it calls maritime and overland “silk roads.” 

China has also pushed for a stronger “periphery diplomacy” to strengthen ties with its neighboring states ― a move that some observers view as Beijing’s attempt to put Asian states under its expanding sphere of influence through a series of bilateral and multilateral economic projects.

China’s increasing influence, coupled with the U.S.’ financial challenges and its attention to conflict-laden zones in other parts of the world, has spawned speculation that Washington might have difficulty stably advancing the rebalance policy.

Cuts in the U.S.’ defense spending have raised questions over whether Washington can keep its vow to bolster its military presence in the Asia-Pacific, while the ongoing campaign against Islamic militants and other terrorist entities in the Middle East and North Africa, have apparently distracted it.

China’s growing economic presence in Southeast Asia has also posed a tricky challenge to the rebalance policy. Washington has been courting Southeast Asian states, which are strategically vital in terms of protecting major sea transport routes for energy and trade, but many of them have seen a delicate balancing act between the U.S. and China to maximize their national interests.

The rebalance policy was crafted as the U.S. realized the urgent need to deepen its engagement in the Asia-Pacific emerging as a fulcrum of global power and wealth, after more than 13 years of ground warfare in Afghanistan and Iraq.

“Rebalance … What it stands for is that we recognize that after so many years of such necessary but strong preoccupation with Iraq and Afghanistan, we need to make sure that we look up and look around and pay adequate attention to what is going on out here,” Carter said during a meeting with U.S. troops in Korea last Thursday.

The U.S. has been pushing for the policy in various ways: through strengthening multilateral diplomacy at institutions such as the East Asia Summit; deepening security alliances and partnerships with regional states including Vietnam, Philippines, Myanmar and Indonesia; and pushing for the Trans-Pacific Partnership, an envisioned free trade deal linking Pacific-rim states.

Amid the continuing doubts over the sustainability of the rebalance, a series of U.S. officials including President Barack Obama and Carter have underscored that the policy remains steadfast, and that their plans to bring in new, state-of-the-art military equipment demonstrate the top priority on this policy.

“All the newest stuff is coming out here, all the most high-tech stuff and all the best stuff is coming out here, and this is where we have strong alliances,” Carter said during the meeting with U.S. troops here.

The “new stuff” to be deployed to the region includes eight ballistic missile defense destroyers to be deployed to Japan through 2017; four littoral combat ships to be deployed to Singapore by 2017; P8 antisubmarine, surveillance aircraft to Japan; the marine squadron of F-35s to Japan; and three DDG-1000 Zumwalt stealth destroyers.

Above all, the most important task concerning the rebalance is to strengthen the U.S.-Japan alliance, which Carter called “the bedrock” of America’s alliance network in the region.

Washington and Tokyo are currently working on revising their 1997 defense cooperation guidelines and seeking to conclude their bilateral negotiations over the Pacific-rim free trade agreement ― the two core elements of the U.S.’ multifaceted engagement in the region.

The revision of the guidelines is expected to contain a set of joint measures to cope with Chinese threats regarding maritime disputes in the East and South China seas, and other emerging scenarios, observers say. First adopted in 1978 to counter Soviet threats, the guidelines were last amended in 1997 to reflect post-Cold War security threats.

Meanwhile, the closer strategic cooperation between the U.S. and Japan is putting pressure on Seoul to enhance its cooperation with the two.

Due to North Korea’s escalating nuclear and missile threats, Seoul shares the need to strengthen security cooperation with Washington and Tokyo. But it is struggling to deal with domestic and diplomatic challenges.

China has opposed stronger trilateral security cooperation among the U.S., South Korea and Japan. Seoul’s security cooperation has also been restricted due to Japan’s failure to fully atone for its wartime wrongdoings amid public calls for more contrition on the part of Japan.

Amid the U.S.’ push for the rebalance, Washington has also sought to strengthen its missile defense ― a reason why the U.S. considers deploying the Terminal High-Altitude Area Defense system, an integral part of its multilayered missile shield.

The THAAD issue has also posed a tricky diplomatic challenge to Seoul as China has strongly opposed the deployment, arguing that it could undermine the regional security balance and cause military tensions.

By Song Sang-ho (sshluck@heraldcorp.com)